In U.S. Pat. Nos. 6,657,334 and 6,831,430, a high phase order induction machine drive system is disclosed. This has an inverter system for the synthesis of a plurality of phases of alternating current output, and a N-phase induction motor (N is greater than 3). The motor is connected to the inverter terminals in the following way: each motor phase is electrically connected to two inverter terminals: a first inverter terminal and a second inverter terminal L inverter terminals distant from the first inverter terminal in order of electrical phase angle (L is the span number). The phase angle difference between the pair of inverter terminals to which each motor phase is connected is identical for each motor phase.
In WO03/092150 several polyphase devices are connected together: an inverter, and electrical rotating machine, and a resistive load or braking resistor. The purpose of the resistive load is to dissipate excess electrical power which may be produced when the inverter acts to slow down the rotating machine, causing the rotating machine to act as a generator. In common art, this resistive load is a single DC resistor coupled to the DC link of the inverter via a separate resistor control transistor. Here, the resistive load is a mesh connected array of resistors, and is electrically connected to the same inverter output terminals that the rotating machine is connected to. When it is desired that the resistors absorb energy, for example from a braking operation, then the harmonic content of the inverter output is adjusted, thus placing voltage differences across the resistor array and causing current to flow in the resistors.
Currently, aircraft either use a tug or use the main engines to taxi. Use of the main engines consumes fuel in a more-or-less inefficient manner, creates pollution (atmospheric and noise), and reduces the effective payload and/or the operating range of an aircraft. Use of a tug reduces pilot control, increases operating costs, and adds to the logistical complexity of airport operations.